1. Field of the Invention
The present invention relates generally to the field of protocol converters. More specifically, the present invention relates to a protocol converter for use with an inertial navigation unit on the P-3 aircraft.
2. Description of the Prior Art
The Department of Homeland Security utilizes airborne surveillance operations to monitor illegal activities which have an impact on national security. These activities include drug trafficking, illegal immigration, and terrorist activities.
Many ride-along sensor units often deployed with a surveillance P-3 aircraft require the implementation the National Marine Electronics Association 0183 (NMEA-0183) serial navigation data format. Future proposed components for geospatial video recording and reproduction also require the ability to utilize this format. There is currently an immediate need to provide aircraft navigation data in real time to produce a coherent video data stream for situational awareness during the transport of sensor video to the ground for analysis. The NMEA-0183 protocol provides a low bandwidth, commonly utilized format that end users can easily make use of for situational awareness.
There are several ARINC-429 to NMEA-0183 protocol converters which are commercially available. None of these converters are specifically designed to utilize the wide variety of parameters available from the Litton LTN-92 Inertial Navigation System (INS), used on the P-3 aircraft, which is manufactured by Litton Industries, Incorporated. These protocol converters extract only the most commonly used parameters from the ARINC-429 protocol (such as time, position, ground speed and heading) and output only a small fixed set of NMEA-0183 sentences (such as RMB, RMC, GGA and GSA). None of the NMEA-0183 sentences provided by these protocol converters are capable of providing pointing information that is used to indicate the location of an object relative to the P-3 aircraft.
Accordingly there is a need for a protocol converter that generates a custom sentence which includes pointing information that is used to indicate the location of an object relative to the P-3 aircraft.